Re: [Maria-developers] Rev 2897: Fix for LP bug#611379. in file:///home/bell/maria/bzr/work-maria-5.1-lb611379/

Hi!

...

...

...

...

"sanja" == sanja writes:

sanja> At file:///home/bell/maria/bzr/work-maria-5.1-lb611379/ sanja> ------------------------------------------------------------ sanja> revno: 2897 sanja> revision-id: sanja@askmonty.org-20100812075534-wc2dngmpiqm9grra sanja> parent: monty@mysql.com-20100809170542-ewa2awm6pcoi1ipy sanja> committer: sanja@askmonty.org sanja> branch nick: work-maria-5.1-lb611379 sanja> timestamp: Thu 2010-08-12 10:55:34 +0300 sanja> message: sanja> Fix for LP bug#611379. sanja> maybe_null/null_value flag set to TRUE for Item_sum_distinct. === modified file 'mysql-test/t/func_group.test' --- a/mysql-test/t/func_group.test 2009-11-24 15:26:13 +0000 +++ b/mysql-test/t/func_group.test 2010-08-12 07:55:34 +0000 @@ -1082,6 +1082,21 @@ from t1 a, t1 b; select *, f1 = f2 from t1; drop table t1; + +--echo # +--echo #test for LP Bug#611379 +--echo # +create table t1 (a int not null); +insert into t1 values (1); +create table t2 (a int not null primary key); +insert into t2 values (10); +explain select sum(distinct t1.a) from t1,t2 where t1.a=t2.a; +explain select * from (select sum(distinct t1.a) from t1,t2 where t1.a=t2.a) +as t; +select sum(distinct t1.a) from t1,t2 where t1.a=t2.a; +select * from (select sum(distinct t1.a) from t1,t2 where t1.a=t2.a) as t; +drop table t1,t2; + --echo # --echo End of 5.1 tests === modified file 'sql/item_sum.cc' --- a/sql/item_sum.cc 2010-08-02 09:01:24 +0000 +++ b/sql/item_sum.cc 2010-08-12 07:55:34 +0000 @@ -949,6 +949,7 @@ { DBUG_ASSERT(args[0]->fixed); + null_value= maybe_null= TRUE; table_field_type= args[0]->field_type(); I don't think you have to set null_value as this is set in item_sum_distinct::setup(), but don't think this is critical to fix. I was checking the Item_sum_num::fix_fields() code and noticed that we do there: maybe_null=0; for (uint i=0 ; i < arg_count ; i++) { if (args[i]->fix_fields(thd, args + i) || args[i]->check_cols(1)) return TRUE; set_if_bigger(decimals, args[i]->decimals); maybe_null |= args[i]->maybe_null; } result_field=0; max_length=float_length(decimals); null_value=1; fix_length_and_dec() I think we can remove from the above all calculation of maybe_null and setting of null_value as fix_length_and_dec() sets maybe_null and null_value. Instead we could add an assert after fix_length_and_dec that maybe_null is set. Regards, Monty